Researchers from Brigham and Women’s Hospital (BWH), in Boston, identified a link between higher caffeine intake in women and lower rates of tinnitus—that irritating sensation of ringing, buzzing, or roaring in the ears that has no external cause. Tinnitus affects roughly one in five people, according to the Mayo Clinic, and often signals another underlying condition, such as an ear injury or hearing loss.

The BWH researchers looked at 65,085 women between the ages of 30 and 44, participants in the National Institutes of Health-funded Nurses’ Health Study II, who were not afflicted by tinnitus at the study’s outset. The participants completed questionnaires on lifestyle, medical history, and food frequency throughout the study period, which ran from 1991 to 2009.

The findings? The women who consumed 450 to 599 mg per day of caffeine (that’s about the amount in 4.5 to 6 eight-ounce cups of coffee) had a 15 percent lower reported incidence of tinnitus at the end of the study than those with an intake of less than 150 mg per day (about 1.5 cups of coffee).

“The reason behind this observed association is unclear,” senior author Gary Curhan, M.D., a physician-researcher in the Channing Division of Network Medicine at BWH and professor of medicine at Harvard Medical School, said in a statement. “We know that caffeine stimulates the central nervous system, and previous research has demonstrated that caffeine has a direct effect on the inner ear in both bench science and animal studies.”

But the results aren’t exactly an Rx for coffee beans: The researchers cautioned that more evidence is needed before making any recommendations as to whether adding caffeine to a patient’s diet could improve tinnitus symptoms.

The research does join a growing body of evidence suggesting possible health benefits of caffeine (in moderation, which experts often define as under 400 mg—less than the 450-599 in this study), and coffee in particular. A cup (or more) of joe—the real stuff, not the 500-calorie-plus dessert varieties—has been linked to reduced risk of Parkinson’s disease, Type 2 diabetes, depression, and liver disease.